Wind power is considered one of the cleanest, most environmentally friendly energy sources presently available, and wind turbines have gained increased attention in this regard. A modern wind turbine typically includes a tower, generator, gearbox, nacelle, and one or more rotor blades. The rotor blades capture kinetic energy of wind using known foil principles. The rotor blades transmit the kinetic energy in the form of rotational energy so as to turn a shaft coupling the rotor blades to a gearbox, or if a gearbox is not used, directly to the generator. The generator then converts the mechanical energy to electrical energy that may be deployed to a utility grid.
The size, shape, and weight of rotor blades are factors that contribute to energy efficiencies of wind turbines. An increase in rotor blade size increases the energy production of a wind turbine, while a decrease in weight also furthers the efficiency of a wind turbine. Presently, large commercial wind turbines in existence and in development are capable of generating from about 1.5 to about 12.5 megawatts of power. These larger wind turbines may have rotor blade assemblies larger than 90 meters in diameter. Accordingly, efforts to increase rotor blade size, decrease rotor blade weight, and increase rotor blade strength, while also improving rotor blade aerodynamics, aid in the continuing growth of wind turbine technology and the adoption of wind energy as an alternative energy source.
As the size of wind turbines increase, particularly the size of rotor blades, so do the respective costs of manufacturing, transporting, and assembling the wind turbines. The economic benefits of increased wind turbine sizes must be weighed against these factors. For example, the costs of pre-forming, transporting, and erecting a wind turbine having rotor blades in the range of 90 meters may significantly impact the economic advantage of the larger wind turbine.
For example, the costs of transporting rotor blades increase as the size of the rotor blades increase. One known method for transporting rotor blades involves the use of large trucks, such as tractor-trailers. The rotor blades are loaded onto trailers, which are hauled by the trucks to a desired destination. Frequently, however, this transportation method is hindered by the existence of obstacles that restrict such transportation. For example, the roadways on which such trucks travel may include turns of varying sizes and shapes. Some such turns in the roads may, for example, require a truck to turn 180 degrees in a relatively short distance. Further, many roads pass by walls, bridges, hills, mountains, trees or other such obstacles that are situated relatively close to the road. Rotor blades having increasing lengths may overhang the trucks on which they are being transported. If a truck is required to turn in a location wherein such obstacles are close to the road, the rotor blades may thus be at risk of contacting the obstacles, resulting in damage to the rotor blades.
Known solutions to these transportation problems require, for example, removing the rotor blade from the truck while the truck is turning. These solutions can be expensive and time-consuming. For example, traffic on the road must be halted, and a crane or other lifting machinery must be utilized to lift the rotor blade from the truck. The truck must then be allowed to turn on the road. The rotor blade must then be replaced and secured on the truck. An alternative solution involves loading the rotor blades into, for example, boats or barges, or trains, rather than trucks, and transporting the rotor blades along waterways or railroads to a desired destination. This solution, however, is also expensive and time-consuming, and frequently the desired destination of a rotor blade does not have waterways or railroads leading to it. A further alternative solution involves separating the rotor blades into smaller separate rotor blade components for transport. However, separating a rotor blade may weaken the fibers and/or other reinforcing structures within the rotor blade, thus undesirably weakening the rotor blade.
Accordingly, improved systems for transporting rotor blades are desired in the art. In particular, transportation systems that are relatively efficient, fast, and cost-effective would be desired.